HI ! I need explaination and solution tq

3. The total profit function and marginal revenue function of a good are given by; IT = 400Q - 5Q- - 200 MR = 500 - 30Q. a) Find the total cost function. b) Find the average cost function. c) Express variable cost function. d) Compute the maximum profit and the value of Q at which it is achieved. e) Compute total cost that would be incurred when profit is maximized